At the same time as the Guy Arab LUFs arrived Pontypridd also took delivery of what was to become their standard double-decker for six years and a double-deck equivalent in the form of the Guy Arab IV. These all had Roe bodies and the Gardner 6LW engine and were probably the closest design on the market to the Bristol K so long favoured by Pontypridd.

The first to arrive were 69/70 (STX 105/6) in 1956 and 1955 respectively. These had Roe H33/25R bodies which featured the Roe staircase window and the safety staircase, the design of which meant that bottom edge was further away from the platform. It also incorporated two landings and the combination improved safety without impacting on seating capacity like a simple straight staircase, employed elsewhere for the same reason. 70 was withdrawn in 1973 but 69 lasted until 1976.

1957 saw the trolleybuses replaced and for this purpose six Guy Arabs arrived. 71-74 (UTX 492-5) and 75/6 (VNY 653/4) arrived that year and were identical to 69/70. The first to be withdrawn was 74 in 1973, 72 in 1974, 71/3 in 1975 and finally 75/6 in 1976.

Three more arrived in 1959. 80-2 (501-3 ATX) were similar but the bodies were H33/26R as they did not have the original design of staircase and this allowed an additional seat downstairs. They didn’t feature the staircase window and also incorporated another new feature - hopper ventilators on 81 and 82, oddly 80 was fitted with sliding ventilators. Although hoppers are virtually standard nowadays they were quite unusual at the time and remained so for while. 80-2 lasted until 1976.

The final Guy Arabs arrived in 1962. 87/8 (872/3 MTG) were nominally the same as 80-2 but were fitted with a different style of bonnet, referred to as the Johannesburg front, which was favoured by Guy for just a short period. They were also Pontypridd’s first eight foot wide double-deckers, all previous ones being 7’-6” wide. These two were also withdrawn in 1976, 87 being among the last four of the type in service.